U.S. patent number 9,180,456 [Application Number 14/163,701] was granted by the patent office on 2015-11-10 for microwell plate.
This patent grant is currently assigned to SABIC GLOBAL TECHNOLOGIES B.V.. The grantee listed for this patent is SABIC Innovative Plastics IP B.V.. Invention is credited to Bret William Baumgarten, Jon M. Malinoski.
United States Patent |
9,180,456 |
Malinoski , et al. |
November 10, 2015 |
Microwell plate
Abstract
A microwell plate is described, including a frame 2 that has a
frame plate 4 made of a first material having holes 2', and a
vessel 3 formlockingly connected to the frame plate 4 and made from
a poly(aliphatic ester)-polycarbonate including soft block ester
units, derived from monomers including an alpha, omega C.sub.6-20
aliphatic dicarboxylic acid or derivative thereof, a
dihydroxyaromatic compound, and a carbonate source.
Inventors: |
Malinoski; Jon M. (Zionsville,
IN), Baumgarten; Bret William (San Rafael, CA) |
Applicant: |
Name |
City |
State |
Country |
Type |
SABIC Innovative Plastics IP B.V. |
Bergen op Zoom |
N/A |
NL |
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Assignee: |
SABIC GLOBAL TECHNOLOGIES B.V.
(NL)
|
Family
ID: |
50156893 |
Appl.
No.: |
14/163,701 |
Filed: |
January 24, 2014 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20140205518 A1 |
Jul 24, 2014 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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61756384 |
Jan 24, 2013 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C08G
63/64 (20130101); C08L 67/02 (20130101); C08L
69/005 (20130101); B01L 3/5085 (20130101); C08L
2666/18 (20130101); B01L 2200/12 (20130101); B01L
2300/0829 (20130101) |
Current International
Class: |
B01L
3/00 (20060101); C08L 67/02 (20060101); C08L
69/00 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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0542422 |
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May 1993 |
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EP |
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605979 |
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Jul 1994 |
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EP |
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1893979 |
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Mar 2008 |
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EP |
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11346772 |
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Dec 2011 |
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EP |
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2007285835 |
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Nov 2007 |
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JP |
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4530895 |
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Aug 2010 |
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JP |
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4706533 |
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Jun 2011 |
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JP |
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0158688 |
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Aug 2001 |
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WO |
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2005028109 |
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Mar 2005 |
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WO |
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WO2006104260 |
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Oct 2006 |
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WO |
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Other References
Copending U.S. Appl. No. 14/163,675, filed Jan. 24, 2014. cited by
applicant .
Copending U.S. Appl. No. 14/163,809, filed Jan. 24, 2014. cited by
applicant .
Notification of Transmittal of the International Search Report and
the Written Opinion; dated May 26, 2014; 5 pgs. cited by applicant
.
Written Opinion of the International Searching Authority; dated May
26, 2014; 5 pgs. cited by applicant.
|
Primary Examiner: Warden; Jill
Assistant Examiner: Krcha; Matthew
Attorney, Agent or Firm: Cantor Colburn LLP
Parent Case Text
This application claims priority on U.S. provisional application
Ser. No. 61/756,384, the disclosure of which is incorporated herein
by reference in its entirety.
Claims
The invention claimed is:
1. A microwell plate comprising: a frame (2) comprising a frame
plate (4) made of a first material having holes (2'), and a vessel
(3) formlockingly connected to the frame plate 4 and made from a
poly(aliphatic ester)-polycarbonate comprising soft block ester
units, derived from monomers comprising: an alpha, omega C.sub.6-20
aliphatic dicarboxylic acid or derivative thereof, a
dihydroxyaromatic compound, and a carbonate source, wherein the
vessel has a wall thickness of less than or equal to 1 mm.
2. The microwell plate of claim 1, wherein the alpha, omega
C.sub.6-20 aliphatic dicarboxylic acid or derivative thereof
comprises sebacic acid.
3. The microwell plate of claim 1, wherein the poly(aliphatic
ester)-polycarbonate is of the formula (6b) ##STR00017## wherein m
is 4 to 18, x and y each represent average weight percentages of
the poly(aliphatic ester)-polycarbonate wherein the average weight
percentage ratio x:y is 10:90 to 1:99, wherein x+y is 100, and each
R.sup.3 is independently derived from a dihydroxyaromatic compound
of formula (3) ##STR00018## wherein Ra and Rb are each
independently a halogen, C1-12 alkoxy, or C1-12 alkyl; Xa is a
single bond, --O--, --S--, --S(O)--, S(O).sub.2--, --C(O)--, or a
C.sub.1-18 organic group; and p and q are each independently
integers of 0 to 4 or formula (5) ##STR00019## wherein each R.sup.h
is independently a halogen atom, a C.sub.1-10 hydrocarbyl such as a
C.sub.1-10 alkyl group, a halogen-substituted C.sub.1-10 alkyl
group, a C.sub.6-10 aryl group, or a halogen-substituted C.sub.6-10
aryl group, and n is 0 to 4.
4. The microwell plate of claim 3, wherein the poly(aliphatic
ester)-polycarbonate is of formula (6c) ##STR00020## wherein m is 4
to 18 and wherein the average weight percentage ratio x:y is 10:90
to 1:99, wherein x+y is 100.
5. The microwell plate of claim 3, wherein m is 8.
6. The microwell plate of claim 1, wherein the poly(aliphatic
ester)-polycarbonate has an MFR of 66 to 150 g/10 min at
300.degree. C. and under a load of 1.2 kilograms according to ASTM
D1238-10.
7. The microwell plate of claim 1, wherein the poly(aliphatic
ester)-polycarbonate has an HDT is 80 to 140.degree. C. at 0.45
mega Pascal (MPa) using unannealed 3.2 mm plaques according to ASTM
D648-07.
8. The microwell plate of claim 7, wherein the poly(aliphatic
ester)-polycarbonate has a Notched Izod Impact (NII) ductility of
30 to 100%, using 1/8-inch thick bars (3.18 mm) at 23.degree. C.
according to ASTM D256-10.
9. The microwell plate of claim 1, wherein the poly(aliphatic
ester)-polycarbonate has an HDT is 80 to 140.degree. C. at 1.82
mega Pascal (MPa) using unannealed 3.2 mm plaques according to ASTM
D648-07.
10. The microwell plate of claim 9, wherein the polu(aliphatic
ester)-polycarbonate has a Notched Izod Impact (NII) ductility of
30 to 100%, using 1/8-inch thick bars (3.18 mm) at 23.degree. C.
according to ASTM D256-10.
11. The microwell plate of claim 1, wherein the poly(aliphatic
ester)-polycarbonate has a Notched Izod Impact (NII) ductility of
30 to 100%, using 1/8-inch thick bars (3.18 mm) at 23.degree. C.
according to with ASTM D256-10.
12. The microwell plate of claim 1, wherein the thermoplastic
composition has a Notched Izod Impact (NII) of 400 to 700 Joules
per meter (Jim) using 1/8-inch thick bars (3.18 mm) at 23.degree.
C. according to with ASTM D256-10.
13. The microwell plate of claim 1, wherein the poly(aliphatic
ester)-polycarbonate is derived from monomers consisting
essentially of the alpha, omega C.sub.6-20 aliphatic dicarboxylic
acid or derivative thereof, the dihydroxyaromatic compound, and the
carbonate source.
14. The microwell plate of claim 1, comprising a plurality of said
vessels.
15. The microwell plate of claim 1, wherein the vessel (3) has a
wall thickness of 0.005 to 1 mm.
16. The microwell plate of claim 1, wherein the vessel (3) has a
wall thickness of 0.01 to 0.5 mm.
17. The microwell plate of claim 1, wherein the vessel (3) has a
wall thickness of 0.05 to 0.2 mm.
18. The microwell plate of claim 1, wherein the vessel (3) has a
collar (12) having two projections (13, 14) thereon that
respectively engage an upper surface (7) and the underside (8) of
the plate (4).
Description
TECHNICAL FIELD
The disclosure generally relates to a microwell plate that utilizes
a thermoplastic composition for with flowability for use in
thin-walled articles.
BACKGROUND
Microwell plates are used for various microbiological, molecular
biological, cellular biological, and immunological procedures. Due
to the high number of samples in each microwell plate, the Society
of Biomolecular screening and the American National Standards
Institute (ANSI) have published standards ANSI/SBS 1-2004 through
4-2004 for microwell plates concerning the particular dimensions
and positions of wells or microwells, herein also referred to as
vessels, for microwell plates having 96, 984, and 1536 wells.
Microwell plates are used in particular for culturing of
microorganisms or cells or for the Polymerase Chain Reaction
(PCR).
PCR is a process used to amplify and copy a piece of DNA sequence
across multiple orders of magnitude and is a vital technique in the
field of molecular biology. In the PCR process, the DNA fragment is
mixed in aqueous solution with complementary DNA primers and DNA
polymerase enzyme and the mixture is taken through several thermal
cycling steps. This thermal cycling process separates the
double-helix of the target DNA sequence and initiates new DNA
synthesis through the DNA polymerase catalyst. A typical thermal
profile for the PCR reaction is shown below in Table 1, where
.degree. C. is degrees Celsius.
TABLE-US-00001 TABLE 1 Step Time Duration Temperature (.degree. C.)
Initial Denaturation 2 minutes 94-95 Denaturation 20-30 seconds
94-95 Primer Extension 1 minute 72 Final Extension 5-15 minutes
72
The PCR reactions are typically carried out in microwells in arrays
from 8 to 96 wells and volumes of 0.2-0.5 milliliters (mL).
Efficient heat transfer through the walls of the microwell to the
reaction solution is required for strict temperature control during
the PCR reaction process. In order to achieve efficient heat
transfer, the PCR trays are designed with very thin microwell wall
thicknesses, such as around 0.2 mm. Injection molding of these
thin-wall trays becomes a significant challenge since an extremely
high flow material is required to fill the thin microwell walls. In
addition, the material needs to have sufficient heat resistance to
avoid deformation during the PCR thermal cycling step, and optical
clarity is desired so the liquid volume level can be observed.
Typically, a polypropylene such as PD702 from LYONDELL BASELL is
used for injection molding of the PCR trays. However, polypropylene
is subject to softening at elevated temperatures such as those used
in PCR denaturation cycles, which can cause PCR or other
microfluidic components to become excessively flexible during
processing, and/or be subject to warping or other physical
deformation, and/or leaking.
Furthermore, single-component microwell plates comprising
polypropylene are not particularly suited for being handled by
automatic devices because their softness makes it difficult for
automatic devices to grip them and their low dimensional stability
can have the consequence that the proportioning needles will
contact the walls while being introduced into the vessels.
Two-component microwell plates comprising a frame plate having a
multiplicity of holes made of a first material that is
formlockingly connected to a multiplicity of vessels (i.e.,
microwells) made from a second material have been proposed, but the
second material must still meet the above-described challenges.
SUMMARY
As further described in detail below, a microwell plate comprises a
frame 2 comprising a frame plate 4 made of a first material having
holes 2', and a vessel 3 formlockingly connected to the frame plate
4 and made from a poly(aliphatic ester)-polycarbonate comprising
soft block ester units, derived from monomers comprising an alpha,
omega C.sub.6-20 aliphatic dicarboxylic acid or derivative thereof,
a dihydroxyaromatic compound, and a carbonate source.
BRIEF DESCRIPTION OF THE DRAWINGS
The following is a brief description of the drawings wherein like
elements are numbered alike and which are presented for the
purposes of illustrating the exemplary embodiments disclosed herein
and not for the purposes of limiting the same:
FIG. 1 shows a microwell plate in an oblique perspective view from
the bottom;
FIG. 2 shows a microwell plate in a largely magnified vertical
section-in-part through the microwell plate of the frame plate and
a vessel; and
FIG. 3 shows a frame plate with 96 holes.
DETAILED DESCRIPTION
This disclosure describes a microwell plate having microwells made
of a high melt flow thermoplastic composition. The microwells can
have wall thicknesses of less than or equal to 1 mm, more
specifically from 0.005 to 1 mm, even more specifically from 0.01
to 0.5 mm, and even more specifically from 0.05 to 0.25 mm. Such
thin walls can help provide achieve efficient heat transfer during
the thermal cycling of the PCR process. The microwell plate
comprises a frame made of a first material, which has a frame plate
with holes, and vessels (i.e., microwells) made from a high melt
flow thermoplastic composition. The vessels are fixedly connected
to the frame plate by directly molding them to the holes, and they
each have a receiving portion protruding from the underside of the
frame plate and are accessible from the upper surface of the frame
plate through apertures. The vessels can be fabricated from a high
melt flow thermoplastic composition exhibiting one or more of
optical clarity, improved modulus, improved room temperature
ductility, heat resistance, oxygen permeability, or a reduced
affinity or neutrality of thermoplastic to DNA or other substances
of the PCR, which can be helpful in applications in thin-wall PCR
microwell trays. Specifically, vessels can be fabricated from a
high melt flow thermoplastic composition polycarbonate comprising a
polyester-polycarbonate copolymer and more specifically a
poly(aliphatic ester)-polycarbonate copolymer. The microwell plate
can also include a lid that can be releasably attached to the upper
surface of the frame. The lid can be made of a rigid material and
can comprise an elastic component between the lid and the
frame.
The frame plate can be fabricated from a stiff plastic. Because of
its stiffness, the frame plate of the microwell plate is
particularly suited for being handled by automatic devices. An edge
can be provided with a bordering protruding from the underside,
which increases its stability and can form a surface to stand on,
and a surface for engagement by the automatic device. The frame
plate can comprise a first material that can be a material such as
aluminum sheet stock, or can comprise a first plastic that can be
an amorphous plastic or a partially crystalline plastic. The first
plastic can be filled or unfilled and can have one or more of a
higher rigidity, a better planarity, a lower tendency to distortion
as compared to the second plastic of the vessels, and can be
capable of withstanding a temperature of at least 100.degree. C.
The first plastic can comprise a polycarbonate and/or a
polypropylene. The first plastic can be filled with for example one
or more of glass, talc, or calcium carbonate. Specific examples of
filled polymers include one or more of glass filled polypropylene,
20 to 40% talc filled polypropylene, or 40 to 60% calcium carbonate
filled polypropylene, and glass filled polycarbonate.
The frame can be made by a multi-component molding technique and
can be made by a two-component molding technique (i.e., a
"twin-shot" technique) or a "three-shot" technique. Each vessel can
be molded directly to a hole associated therewith. Generally, the
vessels can be positively, formlockingly connected to the plate
and/or can be non-positively, frictionally connected with the
plate, and/or be connected by molding the vessels in holes having
varying cross-sections in an axial direction and/or to the marginal
area of the holes on at least one side of the plate, while
connecting them thereto in a non-positive manner. With a vessel
being molded in a hole, it becomes bonded to the plate by the
material the vessel is made of. A formlocking connection is
understood to be a connection in which two connected parts are
provided with inter-engaging elements having complementary forms or
shapes. Upon connection of the two parts, the inter-engaging
complementary elements prevent the two parts from being
disconnected.
The frame plate can be initially molded, with the vessels molded in
a second step subsequent to the molding of the frame plate. In this
manner, any shrinkage of the frame plate plastic that may occur
after molding can occur before the vessels are molded thereto. The
time interval from molding the frame to molding the vessels thereto
can be chosen so that the shrinkage of the frame (e.g. by cooling
it down) essentially is completed. Once the vessels are molded onto
the frame, the frame thereafter maintains the dimensional stability
of the microwell plate and any change in vessel-to-vessel distance
can be confined to very low tolerances of as little as .+-.0.15
millimeters (mm) This dimensional stability can make it easier to
introduce proportioning needles with no wall contact. In order to
facilitate any positioning tolerances, the upper wall region of the
vessels can be designed as a collar of an increased wall
thickness.
Molding the vessels to the plate directly can provide very short
flow paths of the material in molding, which allows achievement of
particularly small wall thicknesses, which can be in the range of
0.05 to 0.25 mm and, in particular, can be 0.1 mm, which can favor
heat transfer. The vessel bottom of each vessel has a gate mark and
from which the material fills the first wall portion of a reduced
wall thickness and an upper wall portion connected to the plate. A
gate mark is a point corresponding to a point in a mold for an
injection-molded part at which a flowable plastic enters the mold.
On a finished part, the gate mark can be visible as, for example,
an uneveness on a surface. The upper wall portion can be designed
as a collar of an increased wall thickness, which allows to
manufacture the microwell plate with particularly small
tolerances.
The microwell plate can further comprise a lid that can be
releasably attached to the upper surface of the frame. The lid can
be made of a rigid material and can comprise an elastic component
between the lid and the frame. When an elastic component is
present, it can be between the lid and the frame and can be fixedly
connected to the lid and/or the frame in order to achieve a good
seal between the lid and the frame. The elastic component can
comprise a thermoplastic, an elastomer, a thermoplastic elastomer,
or a rubber. The seals can be connected to each other for example
by straight-lined webs in the row and/or column directions. The
connection of the elastic component to the frame and/or the lid can
be a non-positive and/or positive and/or by the material of the
vessel when the vessel is bonded to the frame. The elastic
component can be provided on a collar of the vessels. The elastic
component can be annular, plug-shaped, mat-shaped, or lip-shaped.
The lid can be designed such that it can be locked to the
frame.
When the microwell plate comprises a lid, a two-component molding
technique or a three-component molding technique can be employed. A
three-component molding technique can be employed if two different
plastics are used for the frame and vessels and a third plastic is
employed for the elastic component(s). The frame can be molded
initially and the elastic component(s) can be molded to the frame
subsequently and/or the lid can molded initially and the elastic
component(s) can be molded to the lid subsequently. The frame can
be molded integrally with the vessels or the vessels can be molded
in a second step and the elastic component(s) in a third step.
The vessels can have various shapes including pot-shaped,
shell-shaped, cup shaped, cone-shaped, and the like. The vessels
can be cylindrical, spherical, rectangular, hexangular, conical,
and the like. The vessels can also have different shapes in
different sections of the microwell plate. Examples of vessel shape
or configuration include hexagonal or spherical.
Vessels that project from the underside of the plate such as
described herein can be suited for use in thermocyclers for PCR,
since the heat exchange can take place directly between the plate
of the thermocycler and the walls of the vessels. When the vessels
project from the underside of the plate, the vessels can be 3 to 30
mm in diameter and 2 to 15 mm in depth. When the vessels project
beyond the top side of the plate, they can have the advantage of a
sealing attachment of a cover film that can directly fit to the
upper edges of the vessels. When the vessels do not project from
the top side of the plate the plate has the advantage of having a
flat surface such that a cover plate can be laid on top of the
vessels to seal them. The cover plate can be made of any material
such as a glass or a thermoplastic and can have adhesive properties
such as pressure sensitive adhesive properties.
The vessels can further be a laminate structure wherein one or more
layers comprise a high melt flow thermoplastic composition. The
laminate structure can be formed via coextrusion. A laminate
structure can be useful in embodiments where a gas-barrier layer, a
liquid-barrier layer, or the like is desired or to control the
surface properties, for example hydrophobicity. A laminate
structure can also be useful when reagents, such as those used in
PCR techniques, can absorb certain polymers from the substrate
contact with, which potentially reduces the amount of polymer
absorbed and improve reaction yield.
Embodiments will be described with reference to FIGS. 1-3, which
are presented for the purpose of illustrating embodiments and are
not intended to limit the scope of the claims.
Referring now to the Figures, FIGS. 1 and 2 show a microwell plate
1 that comprises a frame 2 and vessels 3. The vessels 3 are made
from a poly(aliphatic ester)-polycarbonate comprising soft block
ester units, derived from monomers comprising an alpha, omega
C.sub.6-20 aliphatic dicarboxylic acid or derivative thereof, a
dihydroxyaromatic compound, and a carbonate source. The frame 2 has
a frame plate 4, the outer edge of which is surrounded by a
bordering 5. At the bottom of the bordering is an expansion 6,
which enables stacking on the upper surface of another microwell
plate 1.
The frame 2 has holes 2' in the frame plate 4. These have a profile
2'' of the cross-section which widens towards the upper surface 7
of the frame plate 4 in two portions of different conicity and
towards the underside 8 of the frame plate 4 in a conical
portion.
The frame 2 can be integrally molded in a first molding step from a
plastic which is relatively rigid when cured. Gate marks are formed
at the edge of frame 2, e.g. at the lower edge of the bordering
5.
At their base, vessels 3 have a cup-shaped bottom 9, which is
bordered by a conical wall portion 10 of a very small wall
thickness (e.g., 0.1 mm) Above it, there is a wall portion 11, the
wall thickness of which gradually increases towards the top. At its
outside, it has the same conicity as the conical wall portion 10.
At its inside, however, it is designed nearly cylindrically, which
results in an approximately wedge shaped profile of the
cross-section.
Wall portion 11 terminates in a collar 12, which also is of an
increased wall thickness with respect to wall portion 10. Vessels 3
are molded to frame plate 4 in the area of collar 12. To this end,
collar 12 externally bears against the inner periphery of holes 2'.
It further has a projection 13, 14 at the upper surface 7 and the
underside 8 of frame plate 4, respectively. With the engagement of
the projections 13, 14 with the upper surface 7 and the underside
8, a formlocking connection of the collar 12 and, thereby, of the
vessel 3 with frame plate 4 is formed.
As shown in FIG. 2, the collar 12 has an outer profile 12' of the
cross-section that widens likewise as the profile 2'' of the hold,
toward the upper surface 7 of the frame plate 4 in two portions of
different conicity and toward the underside 8 of the frame plate 4
in a conical portion, i.e., the cross-sectional profile 2'' of the
hole 2' and the cross-sectional profile 12' of the collar 12 are
complementarily formed. Therefore, a formlocking connection is
already formed when a vessel 3 is inserted in the hole 2'. The
projections 13, 14 only enhance the already formed formlocking
connection. In some embodiments, the collar 12 has only one of the
projections 13 or 14. In other embodiments, both projections are
necessary when the complementary profiles of the vessel 3 and the
hole 2' have a circular cross-section.
Though a specific cross-sectional profile of the hole 2' and the
vessel 3 has been described, it should be understood that they can
have a different shape, e.g. the hole wall can have a convex
profile, with the outer surface of the collar having a concave
profile. Further, the complementary profiles of the hole 2' and the
vessel 3 can be formed of two sections, a cylindrical section and a
conical section widening to the upper surface 7 of the frame plate
4 or to the underside 8. In case the conical section widens toward
the upper surface frame plate 4, the collar 12 is provided with a
bottom projection 14. If the comical section widens to the
underside 8 of the frame plate 4, the collar is provided with the
upper projection 13.
In the area of collar 12, vessels 3 have a cross-section expanding
towards the top in two portions of different conicity. Vessels are
accessible from the upper surface of frame plate 4 through
apertures 15.
The vessels can be simultaneously molded directly to the frame 2
and the holes 2' thereof. Each vessel 3 has its own central gate
mark at the underside of bottom 9. This helps achieve shorter flow
paths of the plastic which are made possible by the particularly
small wall thickness in wall portion 10. The material used is a
high flow polycarbonate, as described herein.
FIG. 3 shows a frame 1' with holes 2'. Holes 2' are accessible from
the top through apertures 15' with an annular sealing 16 made of an
elastic material being disposed around each aperture. Vessels can
be fused or bonded to the frame 1' without the use of interlocking
projections. Alternatively, a non-positive connection can be
produced by placing the seal in an undercut groove in the upper
surface of the frame plate 4.
With the annular sealing 16 present, the apertures 15' can be
sealingly closed by placing a lid (not shown) thereon. The lid can
have approximately the same dimensions of the frame plate 4 and can
be locked into place. The lid can be locked, for example, in the
recesses 17.
Further description of the details of the microwell plates
described herein may be found in U.S. Pat. No. 7,347,977, the
disclosure of which is incorporated herein by reference in its
entirety.
The thermoplastic composition used to make the microfluidic devices
described herein is also referred to as the high flow thermoplastic
composition that comprises polycarbonate, specifically a
polyester-polycarbonate copolymer, more specifically a
poly(aliphatic ester)-polycarbonate copolymer. Generally, as used
herein, the term "polycarbonate" refers to the repeating structural
carbonate units of the formula (1)
##STR00001## in which at least 60 percent of the total number of
R.sup.1 groups contain aromatic moieties and the balance thereof
are aliphatic, alicyclic, or aromatic. Each R.sup.1 can be an
aromatic radical of the formula -A.sup.1-Y.sup.1-A.sup.2-. Each
R.sup.1 can comprise a C.sub.6-30 aromatic group, that is, contains
at least one aromatic moiety. R.sup.1 can be derived from a
dihydroxy compound of the formula HO--R.sup.1--OH, in particular of
formula (2) HO--A.sup.1--Y.sup.1--A.sup.2--OH (2) wherein each of
A.sup.1 and A.sup.2 is a monocyclic divalent aromatic group and
Y.sup.1 is a single bond or a bridging group having one or more
atoms that separate A.sup.1 from A.sup.2. In an embodiment, one
atom separates A.sup.1 from A.sup.2. Illustrative non-limiting
examples of radicals of this type are --O--, --S--, --S(O)--,
S(O).sub.2--, --C(O)--, methylene, cyclohexylmethylene,
2-[2.2.1]-bicycloheptylidene, ethylidene, isopropylidene,
neopentylidene, cyclohexylidene, cyclopentadecylidene,
cyclododecylidene, and adamantylidene. The bridging radical Y.sup.1
can be a hydrocarbon group or a saturated hydrocarbon group such as
methylene, cyclohexylidene, or isopropylidene. Specifically, the
R.sup.1 groups can be derived from a dihydroxy aromatic compound of
formula (3)
##STR00002## wherein R.sup.a and R.sup.b are each independently a
halogen, C.sub.1-12 alkoxy, or C.sub.1-12 alkyl; and p and q are
each independently integers of 0 to 4. It will be understood that
R.sup.a is hydrogen when p is 0, and likewise R.sup.b is hydrogen
when q is 0. Also in formula (3), X.sup.a is a bridging group
connecting the two hydroxy-substituted aromatic groups, where the
bridging group and the hydroxy substituent of each C.sub.6 arylene
group are disposed ortho, meta, or para (specifically para) to each
other on the C.sub.6 arylene group. Examples of the bridging group
X.sup.a include a single bond, --O--, --S--, --S(O)--,
S(O).sub.2--, --C(O)--, or a C.sub.1-18 organic group. The
C.sub.1-18 organic bridging group can be cyclic or acyclic,
aromatic or non-aromatic, and can further comprise heteroatoms such
as halogens, oxygen, nitrogen, sulfur, silicon, or phosphorous. The
C.sub.1-18 organic group can be disposed such that the C.sub.6
arylene groups connected thereto are each connected to a common
alkylidene carbon or to different carbons of the C.sub.1-18 organic
bridging group. In an embodiment, p and q are each 1, and R.sup.a
and R.sup.b are each a C.sub.1-3 alkyl group, specifically methyl,
disposed meta to the hydroxy group on each arylene group. X.sup.a
can be a substituted or unsubstituted C.sub.3-18 cycloalkylidene, a
C.sub.1-25 alkylidene of formula --C(R.sup.c)(R.sup.d)-- wherein
R.sup.c and R.sup.d are each independently hydrogen, C.sub.1-12
alkyl, C.sub.1-12 cycloalkyl, C.sub.7-12 arylalkyl, C.sub.1-12
heteroalkyl, or cyclic C.sub.7-12 heteroarylalkyl, or a group of
the formula --C(.dbd.R.sup.e)-- wherein R.sup.e is a divalent
C.sub.1-12 hydrocarbon group such as methylene,
cyclohexylmethylene, ethylidene, neopentylidene, and
isopropylidene, as well as 2-[2.2.1]-bicycloheptylidene,
cyclohexylidene, cyclopentylidene, cyclododecylidene, or
adamantylidene.
Bisphenols containing substituted or unsubstituted cyclohexane
units can also be used as a dihydroxy compound, for example
bisphenols of the formula (4)
##STR00003## wherein each R.sup.f is independently hydrogen,
C.sub.1-12 alkyl, or halogen; and each R.sup.g is independently
hydrogen or C.sub.1-12 alkyl. The substituents can be aliphatic or
aromatic, straight chain, cyclic, bicyclic, branched, saturated, or
unsaturated. Such cyclohexane-containing bisphenols, for example
the reaction product of two moles of a phenol with one mole of a
hydrogenated isophorone, can be used to make polycarbonate polymers
with high glass transition temperatures and high heat distortion
temperatures. Cyclohexyl bisphenol containing polycarbonates, or a
combination comprising at least one of the foregoing with other
bisphenol polycarbonates, are supplied by BAYER CO. under the APEC*
trade name.
Other aromatic dihydroxy compounds of the formula HO--R.sup.1--OH
include compounds of formula (5)
##STR00004## wherein each R.sup.h is independently a halogen atom,
a C.sub.1-10 hydrocarbyl such as a C.sub.1-10 alkyl group, a
halogen-substituted C.sub.1-10 alkyl group, a C.sub.6-10 aryl
group, or a halogen-substituted C.sub.6-10 aryl group, and n is 0
to 4. The halogen can be bromine.
Some illustrative examples of specific aromatic dihydroxy compounds
include the following: 4,4'-dihydroxybiphenyl,
1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene,
bis(4-hydroxyphenyl)methane, bis(4-hydroxyphenyl)diphenylmethane,
bis(4-hydroxyphenyl)-1-naphthylmethane,
1,2-bis(4-hydroxyphenyl)ethane,
1,1-bis(4-hydroxyphenyl)-1-phenylethane,
2-(4-hydroxyphenyl)-2-(3-hydroxyphenyl)propane,
bis(4-hydroxyphenyl)phenylmethane,
2,2-bis(4-hydroxy-3-bromophenyl)propane,
1,1-bis(hydroxyphenyl)cyclopentane,
1,1-bis(4-hydroxyphenyl)cyclohexane,
1,1-bis(4-hydroxyphenyl)isobutene,
1,1-bis(4-hydroxyphenyl)cyclododecane,
trans-2,3-bis(4-hydroxyphenyl)-2-butene,
2,2-bis(4-hydroxyphenyl)adamantane,
alpha,alpha'-bis(4-hydroxyphenyl)toluene,
bis(4-hydroxyphenyl)acetonitrile,
2,2-bis(3-methyl-4-hydroxyphenyl)propane,
2,2-bis(3-ethyl-4-hydroxyphenyl)propane,
2,2-bis(3-n-propyl-4-hydroxyphenyl)propane,
2,2-bis(3-isopropyl-4-hydroxyphenyl)propane,
2,2-bis(3-sec-butyl-4-hydroxyphenyl)propane,
2,2-bis(3-t-butyl-4-hydroxyphenyl)propane,
2,2-bis(3-cyclohexyl-4-hydroxyphenyl)propane,
2,2-bis(3-allyl-4-hydroxyphenyl)propane,
2,2-bis(3-methoxy-4-hydroxyphenyl)propane,
2,2-bis(4-hydroxyphenyl)hexafluoropropane,
1,1-dichloro-2,2-bis(4-hydroxyphenyl)ethylene,
1,1-dibromo-2,2-bis(4-hydroxyphenyl)ethylene,
1,1-dichloro-2,2-bis(5-phenoxy-4-hydroxyphenyl)ethylene,
4,4'-dihydroxybenzophenone, 3,3-bis(4-hydroxyphenyl)-2-butanone,
1,6-bis(4-hydroxyphenyl)-1,6-hexanedione, ethylene glycol
bis(4-hydroxyphenyl)ether, bis(4-hydroxyphenyl)ether,
bis(4-hydroxyphenyl)sulfide, bis(4-hydroxyphenyl)sulfoxide,
bis(4-hydroxyphenyl)sulfone, 9,9-bis(4-hydroxyphenyl)fluorine,
2,7-dihydroxypyrene,
6,6'-dihydroxy-3,3,3',3'-tetramethylspiro(bis)indane
("spirobiindane bisphenol"), 3,3-bis(4-hydroxyphenyl)phthalimide,
2,6-dihydroxydibenzo-p-dioxin, 2,6-dihydroxythianthrene,
2,7-dihydroxyphenoxathin, 2,7-dihydroxy-9,10-dimethylphenazine,
3,6-dihydroxydibenzofuran, 3,6-dihydroxydibenzothiophene, and
2,7-dihydroxycarbazole, resorcinol, substituted resorcinol
compounds such as 5-methyl resorcinol, 5-ethyl resorcinol, 5-propyl
resorcinol, 5-butyl resorcinol, 5-t-butyl resorcinol, 5-phenyl
resorcinol, 5-cumyl resorcinol, 2,4,5,6-tetrafluoro resorcinol,
2,4,5,6-tetrabromo resorcinol, or the like; catechol; hydroquinone;
substituted hydroquinones such as 2-methyl hydroquinone, 2-ethyl
hydroquinone, 2-propyl hydroquinone, 2-butyl hydroquinone,
2-t-butyl hydroquinone, 2-phenyl hydroquinone, 2-cumyl
hydroquinone, 2,3,5,6-tetramethyl hydroquinone,
2,3,5,6-tetra-t-butyl hydroquinone, 2,3,5,6-tetrafluoro
hydroquinone, 2,3,5,6-tetrabromo hydroquinone, or the like, or
combinations comprising at least one of the foregoing dihydroxy
compounds.
Specific examples of bisphenol compounds of formula (3) include
1,1-bis(4-hydroxyphenyl) methane, 1,1-bis(4-hydroxyphenyl)ethane,
2,2-bis(4-hydroxyphenyl) propane (hereinafter "bisphenol A" or
"BPA"), 2,2-bis(4-hydroxyphenyl) butane,
2,2-bis(4-hydroxyphenyl)octane, 1,1-bis(4-hydroxyphenyl)propane,
1,1-bis(4-hydroxyphenyl) n-butane,
2,2-bis(4-hydroxy-2-methylphenyl)propane,
1,1-bis(4-hydroxy-t-butylphenyl) propane, 3,3-bis(4-hydroxyphenyl)
phthalimidine, 2-phenyl-3,3-bis(4-hydroxyphenyl) phthalimidine
(PPPBP), and 1,1-bis(4-hydroxy-3-methylphenyl)cyclohexane (DMBPC).
Combinations comprising at least one of the foregoing dihydroxy
compounds can also be used.
In some embodiments, the polycarbonate is a linear homopolymer
derived from bisphenol A, in which each of A.sup.1 and A.sup.2 is
p-phenylene and Y.sup.1 is isopropylidene in formula (3).
The polycarbonates can have an intrinsic viscosity, as determined
in chloroform at 25.degree. C., of 0.3 to 1.5 deciliters per gram
(dl/g), specifically 0.45 to 1.0 dug. The polycarbonates can have a
weight average molecular weight (M.sub.w) of 10,000 to 100,000
grams per mole (g/mol), as measured by gel permeation
chromatography (GPC) using a cross-linked styrene-divinyl benzene
column, at a sample concentration of 1 milligram per milliliter,
and as calibrated with polycarbonate standards. The polycarbonate
can have a melt volume flow rate (often abbreviated MVR) that
measures the rate of extrusion of a thermoplastics through an
orifice at a prescribed temperature and load. Polycarbonates for
the formation of articles can have an MVR, measured at 300.degree.
C. under a load of 1.2 kg according to ASTM D1238-10 or ISO 1133,
of 0.5 to 80 cubic centimeters per 10 minutes (cc/10 min).
"Polycarbonates" and "polycarbonate resins" as used herein further
include homopolycarbonates, copolymers comprising different R.sup.1
moieties in the carbonate (referred to herein as
"copolycarbonates"), copolymers comprising carbonate units and
other types of polymer units, such as ester units, polysiloxane
units, and combinations comprising at least one of
homopolycarbonates and copolycarbonates. As used herein,
"combination" is inclusive of blends, mixtures, alloys, reaction
products, and the like. A specific type of copolymer is a polyester
carbonate, also known as a polyester-polycarbonate. Such copolymers
further contain, in addition to recurring carbonate chain units of
the formula (1), units of formula (6)
##STR00005## wherein R.sup.2 is a divalent group derived from a
dihydroxy compound, and can be, for example, a C.sub.2-10 alkylene
group, a C.sub.6-20 alicyclic group, a C.sub.6-20 aromatic group or
a polyoxyalkylene group in which the alkylene groups contain 2 to 6
carbon atoms, specifically 2, 3, or 4 carbon atoms. R.sup.2 can be
a C.sub.2-30 alkylene group having a straight chain, branched
chain, or cyclic (including polycyclic) structure. Alternatively,
R.sup.2 can be derived from an aromatic dihydroxy compound of
formula (3) above, or from an aromatic dihydroxy compound of
formula (5) above. T is a divalent group derived from a
dicarboxylic acid (aliphatic, aromatic, or alkyl aromatic), and can
be, for example, a C.sub.4-18 aliphatic group, a C.sub.6-20
alkylene group, a C.sub.6-20 alicyclic group, a C.sub.6-20 alkyl
aromatic group, or a C.sub.6-20 aromatic group.
Examples of aromatic dicarboxylic acids that can be used to prepare
the polyester units include isophthalic or terephthalic acid,
1,2-di(p-carboxyphenyl)ethane, 4,4'-dicarboxydiphenyl ether,
4,4'-bisbenzoic acid, and combinations comprising at least one of
the foregoing acids. Acids containing fused rings can also be
present, such as in 1,4-, 1,5-, or 2,6-naphthalenedicarboxylic
acids. Specific dicarboxylic acids are terephthalic acid,
isophthalic acid, naphthalene dicarboxylic acid, cyclohexane
dicarboxylic acid, or combinations thereof. A specific dicarboxylic
acid comprises a combination of isophthalic acid and terephthalic
acid wherein the weight ratio of isophthalic acid to terephthalic
acid is 91:9 to 2:98. In another specific embodiment, R.sup.2 is a
C.sub.2-6 alkylene group and T is p-phenylene, m-phenylene,
naphthalene, a divalent cycloaliphatic group, or a combination
thereof. This class of polyester includes the poly(alkylene
terephthalates).
The molar ratio of ester units to carbonate units in the copolymers
can vary broadly, for example 1:99 to 99:1, specifically 10:90 to
90:10, more specifically 25:75 to 75:25, depending on the desired
properties of the final composition.
The thermoplastic composition can comprise a
polyester-polycarbonate copolymer, specifically a
polyester-polycarbonate copolymer in which the ester units of
formula (6) comprise soft block ester units, also referred to
herein as aliphatic dicarboxylic acid ester units. Such a
polyester-polycarbonate copolymer comprising soft block ester units
is also referred to herein as a poly(aliphatic
ester)-polycarbonate. The soft block ester unit can be a C.sub.6-20
aliphatic dicarboxylic acid ester unit (where C.sub.6-20 includes
the terminal carboxyl groups), and can be straight chain (i.e.,
unbranched) or branched chain dicarboxylic acids, cycloalkyl or
cycloalkylidene-containing dicarboxylic acids units, or
combinations of these structural units. In some embodiments, the
C.sub.6-20 aliphatic dicarboxylic acid ester unit includes a
straight chain alkylene group comprising methylene (--CH.sub.2--)
repeating units. In some embodiments, a soft block ester unit
comprises units of formula (6a)
##STR00006## wherein m is 4 to 18, more specifically 8 to 10. The
poly(aliphatic ester)-polycarbonate can include less than or equal
to 25 weight % of the soft block unit. The poly(aliphatic
ester)-polycarbonate can comprise units of formula (6a) in an
amount of 0.5 to 10 weight %, specifically 2 to 9 weight %, and
more specifically 3 to 8 weight %, based on the total weight of the
poly(aliphatic ester)-polycarbonate. The poly(aliphatic
ester)-polycarbonate can have a glass transition temperature of 110
to 145.degree. C., specifically 115 to 145.degree. C., more
specifically 128 to 139.degree. C., even more specifically 130 to
139.degree. C.
The poly(aliphatic ester)-polycarbonate is a copolymer of soft
block ester units with carbonate units. The poly(aliphatic
ester)-polycarbonate is shown in formula (6b)
##STR00007## where each R.sup.3 is independently derived from a
dihydroxyaromatic compound of formula (3) or (5), m is 4 to 18, and
x and y each represent average weight percentages of the
poly(aliphatic ester)-polycarbonate where the average weight
percentage ratio x:y is 10:90 to 0.5:99.5, specifically 9:91 to
1:99, and more specifically 8:92 to 3:97, where x+y is 100.
Soft block ester units, as defined herein, can be derived from an
alpha, omega C.sub.6-20, specifically, C.sub.10-12, aliphatic
dicarboxylic acid or a reactive derivative thereof. The carboxylate
portion of the aliphatic ester unit of formula (6a), in which the
terminal carboxylate groups are connected by a chain of repeating
methylene (--CH.sub.2--) units (where m is as defined for formula
(6a)), can be derived from the corresponding dicarboxylic acid or
reactive derivative thereof, such as the acid halide (specifically,
the acid chloride), an ester, or the like. Exemplary alpha, omega
dicarboxylic acids (from which the corresponding acid chlorides can
be derived) include alpha, omega C.sub.6 dicarboxylic acids such as
hexanedioic acid (also referred to as adipic acid); alpha, omega
C.sub.10 dicarboxylic acids such as decanedioic acid (also referred
to as sebacic acid); and alpha, omega C.sub.12 dicarboxylic acids
such as dodecanedioic acid (sometimes abbreviated as DDDA). It will
be appreciated that the aliphatic dicarboxylic acid is not limited
to these exemplary carbon chain lengths, and that other chain
lengths within the C.sub.6-20 limitation can be used. In some
embodiments, the poly(aliphatic ester)-polycarbonate having soft
block ester units comprising a straight chain methylene group and a
bisphenol A polycarbonate group is shown in formula (6c)
##STR00008## where m is 4 to 18 and x and y are as defined for
formula (6b). In an embodiment, the poly(aliphatic
ester)-polycarbonate copolymer comprises sebacic acid ester units
and bisphenol A carbonate units (formula (6c), where m is 8, and
the average weight ratio of x:y is 6:94).
The poly(aliphatic ester)-polycarbonate copolymer, as described
above, can be a polycarbonate having aliphatic dicarboxylic acid
ester soft block units randomly incorporated along the copolymer
chain. The introduction of the soft block segment (e.g., a flexible
chain of repeating CH.sub.2 units) in the polymer chain of a
polycarbonate reduces the glass transition temperatures (T.sub.g)
of the resulting soft block containing polycarbonate copolymer.
These materials are generally transparent and have higher melt
volume ratios than polycarbonate homopolymers or copolymers without
the soft block.
The poly(aliphatic ester)-polycarbonate copolymer, i.e., a
polycarbonate having aliphatic dicarboxylic acid ester soft block
units randomly incorporated along the copolymer chain, has soft
block segment (e.g., a flexible chain of repeating --CH.sub.2--
units) in the polymer chain, where inclusion of these soft block
segments in a polycarbonate reduces the glass transition
temperatures (T.sub.g) of the resulting soft block-containing
polycarbonate copolymer. These thermoplastic compositions,
comprising soft block in amounts of 0.5 to 10 wt % of the weight of
the poly(aliphatic ester)-polycarbonate, are transparent and have
higher MVR than polycarbonate homopolymers or copolymers without
the soft block.
The poly(aliphatic ester)-polycarbonate can have clarity and light
transmission properties, where a sufficient amount of light with
which to make photometric or fluorometric measurement of specimens
contained within the channels and/or wells of an article made
thereof can pass through the thermoplastic composition. The
poly(aliphatic ester)-polycarbonate can have 80 to 100%
transmission, more specifically, 89 to 100% light transmission as
determined by ASTM D1003-11, using 3.2 mm thick plaques. The
poly(aliphatic ester)-polycarbonate can also have low haze,
specifically 0.001 to 5%, more specifically, 0.001 to 1% as
determined by ASTM D1003-11 using 3.2 mm thick plaques.
While the soft block units of the poly(aliphatic
ester)-polycarbonate copolymers cannot be specifically limited to
the alpha, omega C.sub.6-20 dicarboxylic acids disclosed herein, it
is believed that shorter soft block chain lengths (less than
C.sub.6, including the carboxylic acid groups) cannot provide
sufficient chain flexibility in the poly(aliphatic
ester)polycarbonate to increase the MVR to the desired levels
(i.e., greater than or equal to 13 cc/10 min at 250.degree. C. and
1.2 kg load); likewise, increasing the soft block chain lengths
(greater than C.sub.20, including the carboxylic acid groups) can
result in creation of crystalline domains within the poly(aliphatic
ester)-polycarbonate composition, which in turn can lead to phase
separation of the domains that can manifest as reduced transparency
and increased haze, and can affect the thermal properties such as
T.sub.g (where multiple T.sub.g values can result for different
phase separated domains) and MVR (decreasing MVR to values of less
than 13 cc/10 min at 250.degree. C. and 1.2 kg load).
Exemplary thermoplastic compositions include poly(sebacic acid
ester)-co-(bisphenol A carbonate). It will be understood that a
wide variety of thermoplastic compositions and articles derived
from them can be obtained by not only changing the thermoplastic
compositions (e.g., by replacing sebacic acid with adipic acid in
the poly(sebacic acid ester)-co-(bisphenol A carbonate) but by
changing the amounts of sebacic or other aliphatic acid content in
the blends while maintaining a constant molecular weight or while
varying the molecular weight. Similarly, new thermoplastic
compositions can be identified by changing the molecular weights of
the components in the exemplary copolymer blends while keeping, for
example, sebacic acid content constant.
The ductility, transparency and melt flow of the thermoplastic
compositions may be varied by the composition of the poly(aliphatic
ester)-polycarbonate. For example, wt % of aliphatic dicarboxylic
acid ester units (e.g., sebacic acid) may be varied from 1 to 10 wt
% of the total weight of the thermoplastic composition. The
distribution (in the polymer chain) of the sebacic acid (or other
dicarboxylic acid ester) in the copolymers may also be varied by
choice of synthetic method of the poly(aliphatic
ester)-polycarbonate copolymers (e.g., interfacial, melt processed,
or further reactive extrusion of a low MVR poly(aliphatic
ester)-polycarbonate with a redistribution catalyst) to obtain the
desired properties. In this way, thermoplastic compositions having
high flow (e.g. MVR of up to 25 cc/10 min. at 1.2 Kg and
250.degree. C.) may further be achieved where the poly(aliphatic
ester)-polycarbonate is too low in MVR, or is opaque (where the
soft blocks are too great in length, the concentration of the soft
block in the copolymer is too high, or where the overall molecular
weight of the copolymer is too high, or where the copolymer has a
block architecture in which the soft block units in the copolymer
aggregate to form larger blocks), while transparent products with
greater than or equal to 85% transmission, haze of less than 1%
(measured on a 3.2 mm thick molded plaque), and high flow (e.g., up
to an MVR of 25 cc/10 min. at 1.2 Kg and 250.degree. C.), and
ductility may be obtained. Thermoplastic compositions having this
combination of properties is not obtainable from polycarbonate
compositions of, for example, bisphenol A polycarbonate homopolymer
absent a poly(aliphatic ester)-polycarbonate copolymer.
Polyester-polycarbonate copolymers generally can have a weight
average molecular weight (M.sub.w) of 1,500 to 100,000 grams per
mole (g/mol), specifically 1,700 to 50,000 g/mol. In an embodiment,
poly(aliphatic ester)-polycarbonates have a molecular weight of
15,000 to 45,000 g/mol, specifically 17,000 to 40,000 g/mol, more
specifically 20,000 to 30,000 g/mol, and still more specifically
20,000 to 25,000 g/mol. Molecular weight determinations are
performed using gel permeation chromatography (GPC), using a
cross-linked styrene-divinylbenzene column and calibrated to
polycarbonate references. Samples are prepared at a concentration
of 1 milligram (mg)/mL, and are eluted at a flow rate of 1.0
mL/min.
Polyester-polycarbonates can exhibit melt flow rates as described
by the melt volume ratio (MVR) of 5 to 150 cubic centimeters
(cc)/10 min, specifically 7 to 125 cc/10 min, more specifically 9
to 110 cc/10 min, and still more specifically 10 to 100 cc/10 min,
measured at 300.degree. C. and a load of 1.2 kg according to ASTM
D1238-10. The poly(aliphatic ester)-polycarbonate can have an MVR
of 66 to 150 g/10 min, and more specifically 100 to 150 g/10 min,
measured at 300.degree. C. and under a load of 1.2 kilograms
according to ASTM D1238-10. Commercial polyester blends with
polycarbonate are marketed under the trade name XYLEX.RTM.,
including for example XYLEX.RTM. X7300, and commercial
polyester-polycarbonates are marketed under the trade name
LEXAN.RTM. SLX polymers, including for example LEXAN.RTM. SLX-9000,
and are available from SABIC Innovative Plastics (formerly GE
Plastics). In an embodiment, poly(aliphatic ester)-polycarbonates
have an MVR of 13 to 25 cc/10 min, and more specifically 15 to 22
cc/10 min, measured at 250.degree. C. and under a load of 1.2
kilograms and a dwell time of 6 minutes, according to ASTM
D1238-10. Also in an embodiment, poly(aliphatic
ester)-polycarbonates have an MVR of 13 to 25 cc/10 min, and more
specifically 15 to 22 cc/10 min, measured at 250.degree. C. and
under a load of 1.2 kilograms and a dwell time of 4 minutes,
according to ISO 1133.
The thermoplastic composition can further comprise another
thermoplastic polymer such as a polycarbonate polyester copolymer
different from the poly(aliphatic ester)-polycarbonate copolymer, a
polycarbonate, a polyester, a polysiloxane-polycarbonate copolymer,
or combinations comprising one or more of the foregoing.
The thermoplastic composition can thus comprise poly(aliphatic
ester)-polycarbonate copolymer, and optionally a polycarbonate
polymer not identical to the poly(aliphatic ester)-polycarbonate.
Such added polycarbonate polymer may be included but is not
essential to the thermoplastic composition. In an embodiment, where
desired, the thermoplastic composition may include the
polycarbonate in amounts of less than or equal to 50 wt %, based on
the total weight of poly(aliphatic ester)-polycarbonate and any
added polycarbonate. Specifically useful in the thermoplastic
polymer include homopolycarbonates, copolycarbonates,
polyester-polycarbonates, polysiloxane-polycarbonates, blends
thereof with polyesters, and combinations comprising at least one
of the foregoing polycarbonate-type resins or blends. It should
further be noted that the inclusion of other polymers such as
polycarbonate is permitted provided the desired properties of the
thermoplastic composition are not significantly adversely affected.
In a specific embodiment, a thermoplastic composition consists
essentially of a poly(aliphatic ester)-polycarbonate copolymer. In
another specific embodiment, the thermoplastic composition consists
of poly(aliphatic ester)-polycarbonate copolymer.
When the poly(aliphatic ester)-polycarbonate is blended with other
polymer, the thermoplastic composition can comprise polycarbonate,
including blends of polycarbonate homo and/or copolymers,
polyesters, polyester-polycarbonates other than the poly(aliphatic
ester)-polycarbonates disclosed above, or
polysiloxane-polycarbonate in an amount of less than or equal to 50
wt %, specifically 1 to 50 wt %, and more specifically 10 to 50 wt
%, based on the total weight of poly(aliphatic ester)-polycarbonate
and any added polycarbonate, provided the addition of the
polycarbonate does not significantly adversely affect the desired
properties of the thermoplastic composition. Where a polycarbonate
is used in addition to the poly(aliphatic ester)-polycarbonate, the
polycarbonate (or a combination of polycarbonates, i.e., a
polycarbonate composition) can have an MVR measured at 300.degree.
C. under a load of 1.2 kg according to ASTM D1238-10 or ISO 1133,
of 45 to 75 cc/10 min, specifically 50 to 70 cc/10 min, and more
specifically 55 to 65 cc/10 min.
Polyesters can include, for example, polyesters having repeating
units of formula (6), which include poly(alkylene dicarboxylates),
liquid crystalline polyesters, and polyester copolymers. The
polyesters described herein are generally completely miscible with
the polycarbonates when blended.
Such polyesters generally include aromatic polyesters,
poly(alkylene esters) including poly(alkylene arylates), and
poly(cycloalkylene diesters). Aromatic polyesters can have a
polyester structure according to formula (8), wherein D and T are
each aromatic groups as described hereinabove. In an embodiment,
aromatic polyesters can include, for example,
poly(isophthalate-terephthalate-resorcinol) esters,
poly(isophthalate-terephthalate-bisphenol A) esters,
poly[(isophthalate-terephthalate-resorcinol)
ester-co-(isophthalate-terephthalate-bisphenol A)]ester, or a
combination comprising at least one of these. Also contemplated are
aromatic polyesters with a minor amount, e.g., 0.5 to 10 wt %,
based on the total weight of the polyester, of units derived from
an aliphatic diacid and/or an aliphatic polyol to make
copolyesters. Poly(alkylene arylates) can have a polyester
structure according to formula (8), wherein T comprises groups
derived from aromatic dicarboxylates, cycloaliphatic dicarboxylic
acids, or derivatives thereof. Examples of specific T groups
include 1,2-, 1,3-, and 1,4-phenylene; 1,4- and 1,5-naphthylenes;
cis- or trans-1,4-cyclohexylene; and the like. Specifically, where
T is 1,4-phenylene, the poly(alkylene arylate) is a poly(alkylene
terephthalate). In addition, for poly(alkylene arylate), specific
alkylene groups D include, for example, ethylene, 1,4-butylene, and
bis-(alkylene-disubstituted cyclohexane) including cis- and/or
trans-1,4-(cyclohexylene)dimethylene. Examples of poly(alkylene
terephthalates) include poly(ethylene terephthalate) (PET),
poly(1,4-butylene terephthalate) (PBT), and poly(propylene
terephthalate) (PPT). Poly(alkylene naphthoates), such as
poly(ethylene naphthanoate) (PEN), and poly(butylene naphthanoate)
(PBN), or poly(cycloalkylene diesters) such as
poly(cyclohexanedimethylene terephthalate) (PCT), can also be used.
Combinations comprising at least one of the foregoing polyesters
can also be used.
Copolymers comprising alkylene terephthalate repeating ester units
with other ester groups can also be used. Ester units can include
different alkylene terephthalate units, which can be present in the
polymer chain as individual units, or as blocks of poly(alkylene
terephthalates). Specific examples of such copolymers include
poly(cyclohexanedimethylene terephthalate)-co-poly(ethylene
terephthalate), abbreviated as PETG where the polymer comprises
greater than or equal to 50 mole % of poly(ethylene terephthalate),
and abbreviated as PCTG where the polymer comprises greater than 50
mole % of poly(1,4-cyclohexanedimethylene terephthalate).
Poly(cycloalkylene diester)s can also include poly(alkylene
cyclohexanedicarboxylate)s. Of these, a specific example is
poly(1,4-cyclohexane-dimethanol-1,4-cyclohexanedicarboxylate)
(PCCD), having recurring units of formula (7)
##STR00009## wherein, as described using formula (6), R.sup.2 is a
1,4-cyclohexanedimethylene group derived from
1,4-cyclohexanedimethanol, and T is a cyclohexane ring derived from
cyclohexanedicarboxylate or a chemical equivalent thereof, and can
comprise the cis-isomer, the trans-isomer, or a combination
comprising at least one of the foregoing isomers.
The polyesters can be obtained by interfacial polymerization or
melt-process condensation as described above, by solution phase
condensation, or by transesterification polymerization wherein, for
example, a dialkyl ester such as dimethyl terephthalate can be
transesterified with ethylene glycol using acid catalysis, to
generate poly(ethylene terephthalate). It is possible to use a
branched polyester in which a branching agent, for example, a
glycol having three or more hydroxyl groups or a trifunctional or
multifunctional carboxylic acid has been incorporated. Furthermore,
it is sometimes desirable to have various concentrations of acid
and hydroxyl end groups on the polyester, depending on the ultimate
end use of the composition.
The thermoplastic composition can comprise a
polysiloxane-polycarbonate copolymer, also referred to as a
polysiloxane-polycarbonate. The polysiloxane (also referred to
herein as "polydiorganosiloxane") blocks of the copolymer comprise
repeating siloxane units (also referred to herein as
"diorganosiloxane units") of formula (8):
##STR00010## wherein each occurrence of R is same or different, and
is a C.sub.1-13 monovalent organic radical. For example, R can
independently be a C.sub.1-13 alkyl group, C.sub.1-13 alkoxy group,
C.sub.2-13 alkenyl group, C.sub.2-13 alkenyloxy group, C.sub.3-6
cycloalkyl group, C.sub.3-6 cycloalkoxy group, C.sub.6-14 aryl
group, C.sub.6-10 aryloxy group, C.sub.7-13 arylalkyl group,
C.sub.7-13 arylalkoxy group, C.sub.7-13 alkylaryl group, or
C.sub.7-13 alkylaryloxy group. The foregoing groups can be fully or
partially halogenated with fluorine, chlorine, bromine, or iodine,
or a combination thereof. Combinations of the foregoing R groups
can be used in the same copolymer.
The value of D in formula (8) can vary widely depending on the type
and relative amount of each component in the thermoplastic
composition, the desired properties of the composition, and like
considerations. Generally, D can have an average value of 2 to
1,000, specifically 2 to 500, more specifically 5 to 100. In an
embodiment, D has an average value of 30 to 60, specifically 40 to
60. In another embodiment, D has an average value of 45.
Where D is of a lower value, e.g., less than 40, it can be
desirable to use a relatively larger amount of the
polycarbonate-polysiloxane copolymer. Conversely, where D is of a
higher value, e.g., greater than 40, it can be necessary to use a
relatively lower amount of the polycarbonate-polysiloxane
copolymer.
A combination of a first and a second (or more)
polysiloxane-polycarbonate copolymer can be used, wherein the
average value of D of the first copolymer is less than the average
value of D of the second copolymer. In one embodiment, the
polydiorganosiloxane blocks are provided by repeating structural
units of formula (9):
##STR00011## wherein D is as defined above; each R can
independently be the same or different, and is as defined above;
and each Ar can independently be the same or different, and is a
substituted or unsubstituted C.sub.6-30 arylene radical, wherein
the bonds are directly connected to an aromatic moiety. Ar groups
in formula (9) can be derived from a C.sub.6-30 dihydroxyarylene
compound, for example a dihydroxyarylene compound of formula (2),
(3), or (5) above. Combinations comprising at least one of the
foregoing dihydroxyarylene compounds can also be used. Specific
examples of dihydroxyarylene compounds are 1,1-bis(4-hydroxyphenyl)
methane, 1,1-bis(4-hydroxyphenyl)ethane,
2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(4-hydroxyphenyl)butane,
2,2-bis(4-hydroxyphenyl)octane, 1,1-bis(4-hydroxyphenyl)propane,
1,1-bis(4-hydroxyphenyl).sub.n-butane,
2,2-bis(4-hydroxy-1-methylphenyl)propane,
1,1-bis(4-hydroxyphenyl)cyclohexane, bis(4-hydroxyphenylsulphide),
and 1,1-bis(4-hydroxy-t-butylphenyl)propane. Combinations
comprising at least one of the foregoing dihydroxy compounds can
also be used.
Units of formula (9) can be derived from the corresponding
dihydroxy compound of formula (10)
##STR00012## wherein R, Ar, and D are as described above. Compounds
of formula (10) can be obtained by the reaction of a
dihydroxyarylene compound with, for example, an alpha,
omega-bisacetoxypolydiorgano siloxane under phase transfer
conditions.
In another embodiment, polydiorganosiloxane blocks comprise units
of formula (11)
##STR00013##
wherein R and D are as described above, and each occurrence of
R.sup.5 is independently a divalent C.sub.1-30 alkylene, and
wherein the polymerized polysiloxane unit is the reaction residue
of its corresponding dihydroxy compound. In a specific embodiment,
the polydiorganosiloxane blocks are provided by repeating
structural units of formula (12)
##STR00014## wherein R and D are as defined above. Each R.sup.5 in
formula (12) is independently a divalent C.sub.2-8, aliphatic
group. Each M in formula (12) can be the same or different, and can
be a halogen, cyano, nitro, C.sub.1-8 alkylthio, C.sub.1-8 alkyl,
C.sub.2-8 alkoxy, C.sub.2-8, alkenyl, C.sub.3-8 alkenyloxy group,
C.sub.3-8 cycloalkyl, C.sub.3-8 cycloalkoxy, C.sub.6-10 aryl,
C.sub.6-10 aryloxy, C.sub.7-12 arylalkyl, C.sub.7-12 arylalkoxy,
C.sub.7-12 alkylaryl, or C.sub.7-12 alkylaryloxy, wherein each n is
independently 0, 1, 2, 3, or 4.
In some embodiments, M is bromo or chloro, an alkyl group such as
methyl, ethyl, or propyl, an alkoxy group such as methoxy, ethoxy,
or propoxy, or an aryl group such as phenyl, chlorophenyl, or
tolyl; R.sup.5 is a dimethylene, trimethylene or tetramethylene
group; and R is a C.sub.1-8 alkyl, haloalkyl such as
trifluoropropyl, cyanoalkyl, or aryl such as phenyl, chlorophenyl
or tolyl. In some embodiments, R is methyl, or a mixture of methyl
and trifluoropropyl, or a mixture of methyl and phenyl. In still
another embodiment, M is meth-oxy, n is one, R.sup.5 is a divalent
C.sub.1-3 aliphatic group, and R is methyl.
Units of formula (12) can be derived from the corresponding
dihydroxy polydiorganosiloxane (13)
##STR00015## wherein R, D, M, R.sup.5, and n are as described
above. Such dihydroxy polysiloxanes can be made by effecting a
platinum catalyzed addition between a siloxane hydride of formula
(14)
##STR00016## wherein R and D are as previously defined, and an
aliphatically unsaturated monohydric phenol. Aliphatically
unsaturated monohydric phenols include, for example, eugenol,
2-allylphenol, 4-allyl-2-methylphenol, 4-allyl-2-phenylphenol,
4-allyl-2-bromophenol, 4-allyl-2-t-butoxyphenol,
4-phenyl-2-phenylphenol, 2-methyl-4-propylphenol,
2-allyl-4,6-dimethylphenol, 2-allyl-4-bromo-6-methylphenol,
2-allyl-6-methoxy-4-methylphenol and 2-allyl-4,6-dimethylphenol.
Mixtures comprising at least one of the foregoing can also be
used.
Polysiloxane-polycarbonates comprise 50 to 99.9 wt % of carbonate
units and 0.1 to 50 wt % siloxane units, based on the total weight
of the polysiloxane-polycarbonate. Specific
polysiloxane-polycarbonate copolymers comprise 90 to 99 wt %,
specifically 75 to 99 wt %, of carbonate units and 1 to 25 wt %,
specifically 1 to 10 wt %, siloxane units. An exemplary
polysiloxane-polycarbonate copolymer can comprise 6 wt % siloxane
units. Another exemplary polysiloxane-polycarbonate comprises 20 wt
% siloxane units. All references to weight percent compositions in
the polysiloxane-polycarbonate are based on the total weight of the
polysiloxane-polycarbonate
Exemplary polysiloxane-polycarbonates comprise polysiloxane units
derived from dimethylsiloxane units (e.g., formula (11) where R is
methyl), and carbonate units derived from bisphenol A, e.g., the
dihydroxy compound of formula (3) in which each of A.sup.1 and
A.sup.2 is p-phenylene and Y.sup.1 is isopropylidene.
Polysiloxane-polycarbonates can have a weight average molecular
weight of 2,000 to 100,000 g/mol, specifically 5,000 to 50,000
g/mol. Some specific polysiloxane-polycarbonates have, for example,
a weigh average molecular weight of 15,000 to 45,000 g/mol.
Molecular weights referred to herein are as measured by gel
permeation chromatography using a cross-linked styrene-divinyl
benzene column, at a sample concentration of 1 milligram per
milliliter, and as calibrated with polycarbonate standards.
A polysiloxane-polycarbonate can have a melt volume flow rate,
measured at 300.degree. C. under a load of 1.2 kg, of 1 to 50 cc/10
min, specifically 2 to 30 cc/10 min. In an embodiment, the
polysiloxane-polycarbonate has a melt volume rate measured at
300.degree. C. under a load of 1.2 kg, of 5 to 15 cc/10 min,
specifically 6 to 14 cc/10 min, and specifically 8 to 12 cc/10 min
mixtures of polysiloxane-polycarbonates of different flow
properties can be used to achieve the overall desired flow
property. In an embodiment, exemplary polysiloxane-polycarbonates
are marketed under the trade name LEXAN.RTM. EXL polycarbonates,
available from SABIC Innovative Plastics (formerly GE
Plastics).
The thermoplastic composition can further include various other
additives ordinarily incorporated with thermoplastic compositions
of this type, where the additives are selected so as not to
significantly adversely affect the desired properties of the
thermoplastic composition. Mixtures of additives can be used. Such
additives can be mixed at a suitable time during the mixing of the
components for forming the thermoplastic composition.
Additives contemplated herein include, but are not limited to,
impact modifiers, fillers, colorants including dyes and pigments,
antioxidants, heat stabilizers, light and/or UV light stabilizers,
reinforcing agents, light reflecting agents, surface effect
additives, plasticizers, lubricants, mold release agents, flame
retardants, antistatic agents, anti-drip agents, radiation (gamma)
stabilizers, and the like, or a combination comprising at least one
of the foregoing additives. A combination of additives can be used,
for example a combination of a heat stabilizer, mold release agent,
and ultraviolet light stabilizer. Specifically, a combination of
additives can be used comprising one or more of an antioxidant such
as IRGAPHOS*, pentaerythritol stearate, a compatibilizer such as
JONCRYL* epoxy, a quaternary ammonium compound such as tetramethyl
ammonium hydroxide or tetrabutyl ammonium hydroxide, and a
quaternary phosphonium compound such as tetrabutyl phosphonium
hydroxide or tetrabutyl phosphonium acetate. In general, the
additives are used in the amounts generally known to be effective.
The total amount of additives (other than any impact modifier,
filler, or reinforcing agents) is generally 0.01 to 5 weight %,
based on the total weight of the composition. While it is
contemplated that other resins and/or additives can be used in the
thermoplastic compositions described herein, such additives while
desirable in some exemplary embodiments are not essential.
The thermoplastic composition can comprise poly(aliphatic
ester)-polycarbonate in an amount of 50 to 100 wt %, based on the
total weight of poly(aliphatic ester)-polycarbonate and any added
polycarbonate. The thermoplastic composition can comprise only
poly(aliphatic ester)-polycarbonate. The thermoplastic composition
can comprise poly(aliphatic ester)-polycarbonate that has been
reactively extruded to form a reaction product. The thermoplastic
composition can comprise a blend of poly(aliphatic
ester)-polycarbonate that has been reactively extruded.
The thermoplastic composition can comprise a soft block content
(i.e., an alpha, omega C.sub.6-20 dicarboxylic acid ester unit
content) of 0.5 to 10 wt %, specifically 1 to 9 wt %, and more
specifically 3 to 8 wt %, based on the total weight of the
poly(aliphatic ester)-polycarbonate copolymer and any added
polycarbonate.
The thermoplastic composition can have clarity and light
transmission properties, where a sufficient amount of light with
which to make photometric or fluorometric measurement of specimens
contained within the channels and/or wells of an article made
thereof can pass through the thermoplastic composition.
Thermoplastic composition can have 80 to 100% transmission, more
specifically, 89 to 100% light transmission as determined by ASTM
D1003-11, using 3.2 mm thick plaques. The thermoplastic composition
can also have low haze, specifically 0.001 to 5%, more
specifically, 0.001 to 1% as determined by ASTM D1003-11 using 3.2
mm thick plaques.
The thermoplastic composition can have an MVR of greater than or
equal to 13 cc/10 min, specifically of 13 to 25 cc/10 min at
300.degree. C. under a load of 1.2 kg), more specifically of 15 to
22 cc/10 min at 300.degree. C. under a load of 1.2 kg according to
ASTM D1238-10.
The thermoplastic compositions can further have an HDT of greater
than or equal to 100.degree. C., more specifically of 100 to
140.degree. C. measured at 1.82 mega Pascal (MPa) using unannealed
3.2 mm plaques according to ASTM D648-07. The thermoplastic
compositions can also have an HDT of greater than or equal to
115.degree. C., more specifically of 115 to 155.degree. C. measured
at 0.45 MPa using unannealed 3.2 mm plaques according to ASTM
D648-07.
The thermoplastic compositions can further have a Notched Izod
Impact of 400 to 700 Joules per meter (J/m) or 510 to 650 J/m,
measured at 23.degree. C. using 1/8-inch thick bars (3.18 mm) in
accordance with ASTM D256-10. The thermoplastic compositions can
further have a Notched Izod Impact ductilities of 30 to 100% or 50
to 100%, measured at 23.degree. C. using 1/8-inch thick bars (3.18
mm) in accordance with ASTM D256-10.
The thermoplastic compositions can have an instrumented impact
energy at peak of 40 to 80 J/m or 50 to 70 J/m, measured at
23.degree. C. in accordance with ASTM D3763-10. The thermoplastic
compositions can have an instrumented impact ductility of 65 to
100% or 85 to 100% measured at 23.degree. C. in accordance with
ASTM D3763-10.
The thermoplastic compositions can have a tensile or a flexural
modulus of 1500 to 3500 MPa or 2000 to 3000 MPa measured at 0.2
inches (in)/min (approximately 5.0 mm/min) in accordance with ASTM
D638-10. The thermoplastic compositions can have a tensile stress
at yield of 35 to 100 MPa or 50 to 80 MPa measured at 0.2 in/min in
accordance with ASTM D638-10. The thermoplastic compositions can
have a tensile stress at break of 35 to 100 MPa or 50 to 80 MPa
measured at 0.2 in/min in accordance with ASTM D638-10. The
polycarbonate compositions can have a tensile strain at yield of 2
to 10% or 5 to 8% measured at 0.2 in/min in accordance with ASTM
D638-10. The thermoplastic compositions can have a tensile strain
at break of 85 to 150% or 95 to 110% measured at 0.2 in/min in
accordance with ASTM D638-10.
Polycarbonates and polyestercarbonates can be manufactured by
processes such as interfacial polymerization and melt
polymerization. Although the reaction conditions for interfacial
polymerization can vary, an exemplary process generally involves
dissolving or dispersing a dihydric phenol reactant in aqueous
caustic soda or potash, adding the resulting mixture to a
water-immiscible solvent medium, and contacting the reactants with
a carbonate precursor in the presence of a catalyst such as, for
example, a tertiary amine or a phase transfer catalyst, under
controlled pH conditions, e.g., 8 to 10. The most commonly used
water immiscible solvents include methylene chloride,
1,2-dichloroethane, chlorobenzene, toluene, and the like.
Exemplary carbonate precursors include, for example, a carbonyl
halide such as carbonyl bromide or carbonyl chloride, or a
haloformate such as a bishaloformates of a dihydric phenol (e.g.,
the bischloroformates of bisphenol A, hydroquinone, or the like) or
a glycol (e.g., the bishaloformate of ethylene glycol, neopentyl
glycol, polyethylene glycol, or the like). Combinations comprising
at least one of the foregoing types of carbonate precursors can
also be used. In an exemplary embodiment, an interfacial
polymerization reaction to form carbonate linkages uses phosgene as
a carbonate precursor, and is referred to as a phosgenation
reaction.
Among tertiary amines that can be used are aliphatic tertiary
amines such as triethylamine, tributylamine, cycloaliphatic amines
such as N,N-diethyl-cyclohexylamine and aromatic tertiary amines
such as N,N-dimethylaniline.
Among the phase transfer catalysts that can be used are catalysts
of the formula (R.sup.3).sub.4Q.sup.+X, wherein each R.sup.3 is the
same or different, and is a C.sub.1-10 alkyl group; Q is a nitrogen
or phosphorus atom; and X is a halogen atom or a C.sub.1-8 alkoxy
group or C.sub.6-18 aryloxy group. Exemplary phase transfer
catalysts include, for example, [CH.sub.3(CH.sub.2).sub.3].sub.4NX,
[CH.sub.3(CH.sub.2).sub.3].sub.4PX,
[CH.sub.3(CH.sub.2).sub.5].sub.4NX,
[CH.sub.3(CH.sub.2).sub.6].sub.4NX,
[CH.sub.3(CH.sub.2).sub.4].sub.4NX,
CH.sub.3[CH.sub.3(CH.sub.2).sub.3].sub.3NX, and
CH.sub.3[CH.sub.3(CH.sub.2).sub.2].sub.3NX, wherein X is Cl.sup.-,
Br.sup.-, a C.sub.1-8 alkoxy group or a C.sub.6-18 aryloxy group.
An effective amount of a phase transfer catalyst can be 0.1 to 10
weight percent (wt %) based on the weight of bisphenol in the
phosgenation mixture. In another embodiment, an effective amount of
phase transfer catalyst can be 0.5 to 2 wt % based on the weight of
bisphenol in the phosgenation mixture.
When an interfacial polymerization is used as the polymerization
method, rather than utilizing the dicarboxylic acid (such as the
alpha, omega C.sub.6-20 aliphatic dicarboxylic acid) per se, it is
possible to employ the reactive derivatives of the dicarboxylic
acid, such as the corresponding dicarboxylic acid halides, and in
particular the acid dichlorides and the acid dibromides. Thus, for
example instead of using isophthalic acid, terephthalic acid, or a
combination comprising at least one of the foregoing (for
poly(arylate ester)-polycarbonates), it is possible to employ
isophthaloyl dichloride, terephthaloyl dichloride, and a
combination comprising at least one of the foregoing. Similarly,
for the poly(aliphatic ester)-polycarbonates, it is possible to
use, for example, acid chloride derivatives such as a C.sub.6
dicarboxylic acid chloride (adipoyl chloride), a C.sub.10
dicarboxylic acid chloride (sebacoyl chloride), or a C.sub.12
dicarboxylic acid chloride (dodecanedioyl chloride). The
dicarboxylic acid or reactive derivative can be condensed with the
dihydroxyaromatic compound in a first condensation, followed by in
situ phosgenation to generate the carbonate linkages with the
dihydroxyaromatic compound. Alternatively, the dicarboxylic acid or
derivative can be condensed with the dihydroxyaromatic compound
simultaneously with phosgenation.
Alternatively, melt processes can be used to make the
polycarbonates. Generally, in the melt polymerization process,
polycarbonates can be prepared by co-reacting, in a molten state,
the dihydroxy reactant(s) and a diaryl carbonate ester, such as
diphenyl carbonate, in the presence of a transesterification
catalyst in a BANBURY* mixer, twin screw extruder, or the like to
form a uniform dispersion. Volatile monohydric phenol is removed
from the molten reactants by distillation and the polymer is
isolated as a molten residue. A specific melt process for making
polycarbonates uses a diaryl carbonate ester having
electron-withdrawing substituents on the aryls. Examples of
specific diaryl carbonate esters with electron withdrawing
substituents include bis(4-nitrophenyl)carbonate,
bis(2-chlorophenyl)carbonate, bis(4-chlorophenyl)carbonate,
bis(methyl salicyl)carbonate, bis(4-methylcarboxylphenyl)carbonate,
bis(2-acetylphenyl)carboxylate, bis(4-acetylphenyl)carboxylate, or
a combination comprising at least one of the foregoing. In
addition, transesterification catalysts for use can include phase
transfer catalysts of formula (R.sup.4).sub.4QA above, wherein each
R.sup.4, Q, and X are as defined above. Examples of
transesterification catalysts include tetrabutylammonium hydroxide,
methyltributylammonium hydroxide, tetrabutylammonium acetate,
tetrabutylphosphonium hydroxide, tetrabutylphosphonium acetate,
tetrabutylphosphonium phenolate, or a combination comprising at
least one of the foregoing.
All types of polycarbonate end groups are contemplated in the
polycarbonate composition, provided that such end groups do not
significantly adversely affect desired properties of the
compositions.
Branched polycarbonate blocks can be prepared by adding a branching
agent during polymerization. These branching agents include
polyfunctional organic compounds containing at least three
functional groups selected from hydroxyl, carboxyl, carboxylic
anhydride, haloformyl, and mixtures of the foregoing functional
groups. Specific examples include trimellitic acid, trimellitic
anhydride, trimellitic trichloride, tris-p-hydroxy phenyl ethane,
isatin-bisphenol, tris-phenol TC
(1,3,5-tris((p-hydroxyphenyl)isopropyl)benzene), tris-phenol PA
(4(4(1,1-bis(p-hydroxyphenyl)-ethyl)alpha, alpha-dimethyl
benzyl)phenol), 4-chloroformyl phthalic anhydride, trimesic acid,
and benzophenone tetracarboxylic acid. The branching agents can be
added at a level of 0.05 to 2.0 weight %. Mixtures comprising
linear polycarbonates and branched polycarbonates can be used.
A chain stopper (also referred to as a capping agent) can be
included during polymerization. The chain stopper limits molecular
weight growth rate, and so controls molecular weight in the
polycarbonate. Exemplary chain stoppers include certain
mono-phenolic compounds, mono-carboxylic acid chlorides, and/or
mono-chloroformates. Mono-phenolic chain stoppers are exemplified
by monocyclic phenols such as phenol and C.sub.1-22
alkyl-substituted phenols such as p-cumyl-phenol, resorcinol
monobenzoate, and p- and tertiary-butyl phenol; and monoethers of
diphenols, such as p-methoxyphenol. Alkyl-substituted phenols with
branched chain alkyl substituents having 8 to 9 carbon atom can be
specifically mentioned. Certain mono-phenolic UV absorbers can also
be used as a capping agent, for example
4-substituted-2-hydroxybenzophenones and their derivatives, aryl
salicylates, monoesters of diphenols such as resorcinol
monobenzoate, 2-(2-hydroxyaryl)-benzotriazoles and their
derivatives, 2-(2-hydroxyaryl)-1,3,5-triazines and their
derivatives, and the like.
Mono-carboxylic acid chlorides can also be used as chain stoppers.
These include monocyclic, mono-carboxylic acid chlorides such as
benzoyl chloride, C.sub.1-22 alkyl-substituted benzoyl chloride,
toluoyl chloride, halogen-substituted benzoyl chloride,
bromobenzoyl chloride, cinnamoyl chloride, 4-nadimidobenzoyl
chloride, and combinations thereof; polycyclic, mono-carboxylic
acid chlorides such as trimellitic anhydride chloride, and
naphthoyl chloride; and combinations of monocyclic and polycyclic
mono-carboxylic acid chlorides. Chlorides of aliphatic
monocarboxylic acids with less than or equal to 22 carbon atoms are
useful. Functionalized chlorides of aliphatic monocarboxylic acids,
such as acryloyl chloride and methacryoyl chloride, are also
useful. Also useful are monochloroformates including monocyclic,
mono-chloroformates, such as phenyl chloroformate,
alkyl-substituted phenyl chloroformate, p-cumyl phenyl
chloroformate, toluene chloroformate, and combinations thereof.
Where the melt volume rate of an otherwise compositionally suitable
poly(aliphatic ester)-polycarbonate is not suitably high, i.e.,
where the MVR is less than 13 cc/10 min when measured at
250.degree. C., under a load of 1.2 kg, the poly(aliphatic
ester)-polycarbonate can be modified to provide a reaction product
with a higher flow (i.e., greater than or equal to 13 cc/10 min
when measured at 250.degree. C., under a load of 1.2 kg), by
treatment using a redistribution catalyst under conditions of
reactive extrusion. During reactive extrusion, the redistribution
catalyst can be typically included in small amounts of less than or
equal to 400 parts per million (ppm) by weight, by injecting a
dilute aqueous solution of the redistribution catalyst into the
extruder being fed with the poly(aliphatic
ester)-polycarbonate.
The redistribution catalyst can be tetraalkylphosphonium hydroxide,
tetraalkylphosphonium alkoxide, tetraalkylphosphonium aryloxide, a
tetraalkylphosphonium carbonate, a tetraalkylammonium hydroxide, a
tetraalkylammonium carbonate, a tetraalkylammonium phosphite, a
tetraalkylammonium acetate, or a combination comprising at least
one of the foregoing catalysts, wherein each alkyl is independently
a C.sub.1-6 alkyl. In a specific embodiment, a redistribution
catalyst is a tetra C.sub.1-6 alkylphosphonium hydroxide, C.sub.1-6
alkyl phosphonium phenoxide, or a combination comprising one or
more of the foregoing catalysts. An exemplary redistribution
catalyst is tetra-n-butylphosphonium hydroxide.
The redistribution catalyst can be present in an amount of 40 to
120 ppm, specifically 40 to 110 ppm, and more specifically 40 to
100 ppm, by weight based on the weight of the poly(aliphatic
ester)-polycarbonate.
The thermoplastic compositions described herein can be molded into
shaped articles by for example injection molding (such as one-shot
or two-shot injection molding), extrusion, rotational molding, blow
molding, and thermoforming. Desirably, the thermoplastic
composition has excellent mold filling capability due to its high
flow properties.
The thermoplastic composition can be manufactured, for example, by
mixing powdered poly(aliphatic ester)-polycarbonate copolymer,
along with an added polycarbonate and/or additives in a HENSCHEL
MIXER* high speed mixer. Other low shear processes including but
not limited to hand mixing can also accomplish this blending. The
blend can then fed into the throat of an extruder via a hopper.
Alternatively, one or more of the components can be incorporated
into the composition by feeding directly into the extruder at the
throat and/or downstream through a sidestuffer. Additives can also
be compounded into a masterbatch with a desired polymeric resin and
fed into the extruder. The extruder is generally operated at a
temperature higher than that necessary to cause the composition to
flow, but at which temperature components of the thermoplastic
composition do not decompose so as to significantly adversely
affect the composition. The extrudate is immediately quenched in a
water bath and pelletized. The pellets, so prepared when cutting
the extrudate, can be one-fourth inch long or less as desired. Such
pellets can be used for subsequent molding, shaping, or
forming.
In a specific embodiment, the compounding extruder is a twin-screw
extruder. The extruder is typically operated at a temperature of
180 to 385.degree. C., specifically 200 to 330.degree. C., more
specifically 220 to 300.degree. C., wherein the die temperature can
be different. The extruded thermoplastic composition is quenched in
water and pelletized.
Further description of the details of the high flow thermoplastic
composition comprising polycarbonate in U.S. patent application
Ser. No. 61/756,378 filed on Jan. 24, 2013 under attorney docket
number 12PLAS0016-US-PSP, entitled "Polycarbonate Microfluidic
Articles", the disclosure of which is incorporated herein by
reference in its entirety.
All ranges disclosed herein are inclusive of the endpoints, and the
endpoints are independently combinable with each other (e.g.,
ranges of "up to 25 weight %, or, more specifically, 5 weight % to
20 weight %", is inclusive of the endpoints and all intermediate
values of the ranges of "5 weight % to 25 weight %," etc.).
"Combination" is inclusive of blends, mixtures, alloys, reaction
products, and the like. Furthermore, the terms "first," "second,"
and the like, herein do not denote any order, quantity, or
importance, but rather are used to denote one element from another.
The terms "a" and "an" and "the" herein do not denote a limitation
of quantity, and are to be construed to cover both the singular and
the plural, unless otherwise indicated herein or clearly
contradicted by context. The suffix "(s)" as used herein is
intended to include both the singular and the plural of the term
that it modifies, thereby including one or more of that term (e.g.,
the film(s) includes one or more films). Reference throughout the
specification to "one embodiment", "another embodiment", "an
embodiment", and so forth, means that a particular element (e.g.,
feature, structure, and/or characteristic) described in connection
with the embodiment is included in at least one embodiment
described herein, and can or cannot be present in other
embodiments. In addition, it is to be understood that the described
elements can be combined in any suitable manner in the various
embodiments.
The terms "bottom" and/or "top" are used herein, unless otherwise
noted, merely for convenience of description, and are not limited
to any one position or spatial orientation.
The endpoints of all ranges directed to the same component or
property are inclusive and independently combinable (e.g., ranges
of "less than or equal to 25 weight %, or 5 weight % to 20 weight
%," is inclusive of the endpoints and all intermediate values of
the ranges of "5 weight % to 25 weight %," etc.).
As used herein, the term "hydrocarbyl" and "hydrocarbon" refers
broadly to a substituent comprising carbon and hydrogen, optionally
with 1 to 3 heteroatoms, for example, oxygen, nitrogen, halogen,
silicon, sulfur, or a combination thereof; "alkyl" refers to a
straight or branched chain, saturated monovalent hydrocarbon group;
"alkylene" refers to a straight or branched chain, saturated,
divalent hydrocarbon group; "alkylidene" refers to a straight or
branched chain, saturated divalent hydrocarbon group, with both
valences on a single common carbon atom; "alkenyl" refers to a
straight or branched chain monovalent hydrocarbon group having at
least two carbons joined by a carbon-carbon double bond;
"cycloalkyl" refers to a non-aromatic monovalent monocyclic or
multicylic hydrocarbon group having at least three carbon atoms,
"cycloalkenyl" refers to a non-aromatic cyclic divalent hydrocarbon
group having at least three carbon atoms, with at least one degree
of unsaturation; "aryl" refers to an aromatic monovalent group
containing only carbon in the aromatic ring or rings; "arylene"
refers to an aromatic divalent group containing only carbon in the
aromatic ring or rings; "alkylaryl" refers to an aryl group that
has been substituted with an alkyl group as defined above, with
4-methylphenyl being an exemplary alkylaryl group; "arylalkyl"
refers to an alkyl group that has been substituted with an aryl
group as defined above, with benzyl being an exemplary arylalkyl
group; "acyl" refers to an alkyl group as defined above with the
indicated number of carbon atoms attached through a carbonyl carbon
bridge (--C(.dbd.O)--); "alkoxy" refers to an alkyl group as
defined above with the indicated number of carbon atoms attached
through an oxygen bridge (--O--); and "aryloxy" refers to an aryl
group as defined above with the indicated number of carbon atoms
attached through an oxygen bridge (--O--).
Unless otherwise indicated, each of the foregoing groups can be
unsubstituted or substituted, provided that the substitution does
not significantly adversely affect synthesis, stability, or use of
the compound. The term "substituted" as used herein means that at
least one hydrogen on the designated atom or group is replaced with
another group, provided that the designated atom's normal valence
is not exceeded. When the substituent is oxo (i.e., .dbd.O), then
two hydrogens on the atom are replaced. Combinations of
substituents and/or variables are permissible provided that the
substitutions do not significantly adversely affect synthesis or
use of the compound. Exemplary groups that can be present on a
"substituted" position include, but are not limited to, cyano;
hydroxyl; nitro; azido; alkanoyl (such as a C.sub.2-6 alkanoyl
group such as acyl); carboxamido; C.sub.1-6 or C.sub.1-3 alkyl,
cycloalkyl, alkenyl, and alkynyl (including groups having at least
one unsaturated linkages and from 2 to 8, or 2 to 6 carbon atoms);
C.sub.1-6 or C.sub.1-3 alkoxy groups; C.sub.6-10 aryloxy such as
phenoxy; C.sub.1-6 alkylthio; C.sub.1-6 or C.sub.1-3 alkylsulfinyl;
C.sub.1-6 or C.sub.1-3 alkylsulfonyl; aminodi(C.sub.1-6 or
C.sub.1-3)alkyl; C.sub.6-12 aryl having at least one aromatic rings
(e.g., phenyl, biphenyl, naphthyl, or the like, each ring either
substituted or unsubstituted aromatic); C.sub.7-19 alkylenearyl
having 1 to 3 separate or fused rings and from 6 to 18 ring carbon
atoms, with benzyl being an exemplary arylalkyl group; or
arylalkoxy having 1 to 3 separate or fused rings and from 6 to 18
ring carbon atoms, with benzyloxy being an exemplary arylalkoxy
group.
All cited patents, patent applications, and other references are
incorporated herein by reference in their entirety. However, if a
term in the present application contradicts or conflicts with a
term in the incorporated reference, the term from the present
application takes precedence over the conflicting term from the
incorporated reference.
While the disclosure has been described with reference to an
exemplary embodiment, it will be understood by those skilled in the
art that various changes can be made and equivalents can be
substituted for elements thereof without departing from the scope
of the disclosure. In addition, many modifications can be made to
adapt a particular situation or material to the teachings of the
disclosure without departing from the essential scope thereof.
Therefore, it is intended that the disclosure not be limited to the
particular embodiment disclosed as the best mode contemplated for
carrying out this disclosure, but that the disclosure will include
all embodiments falling within the scope of the appended
claims.
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